let inConfig = {
  $dir: __dirname,
  $out: __dirname,
  $src: __dirname,
  $: __dirname
}

class HelperUnit {
  constructor(config = null) {
    this.config = config || inConfig;
    this.regEx = {};
    this.buildRegex();
  }

  static setGlobalConfig(config) {
    inConfig = config;
  }

  addConfigItem(name, value, regexOnly = false) {
    if (!regexOnly) {
      this.config[name] = value;
    }
    let replace = name.replace("$", "\\$");
    this.regEx[name] = new RegExp(`(${replace})`, "gm");
  }

  setConfig(config) {
    this.config = config;
    this.buildRegex();
  }

  buildRegex() {
    const keys = Object.keys(this.config);
    this.regEx = {};
    for (const key of keys) {
      this.addConfigItem(key, null, true);
    }
  }

  replaceVariables(string) {
    const keys = Object.keys(this.config);
    for (const key of keys) {
      string = string.replace(this.regEx[key], this.config[key]);
    }
    return string;
  }

  clone() {
    return new HelperUnit(this.config);
  }
}
module.exports = HelperUnit;